Steelojames I'd be fuming, too.
but to be honestly some people are waiting up to 3 months for a new passport so 3 weeks later isn't to bad tbh
The people who are waiting upto 3 months haven't paid through the nose for a fast track, guaranteed 8 day turnaround, though!
The people who are waiting 3 months have paid the standard fee.
You should have received your sons passport 21 days ago
!!
Contact your MP, asap, Steelojames.
As for the old passport being sent to your dad's address, I don't see that's your fault, either.
Just to put it into context, I applied for two adult passports, 1 of which was a first adult passport (17 year old DD), and three children's passport (one was a first passport).
The appointment at Liverpool was last Thursday, and we'd received them all by Tuesday of this week. The marriage and birth certificates arrived this morning.
We didn't even pay for ours till Monday of this week due to a mix up on my part of thinking I could pay using a mandate form, rather than actually having the card to pass onto the cashier.
The cashier didn't have the facilities to do the payment unless he had the card, but he arranged for the other team to call me, as they had the facilities to receive payment over the phone. They called us too! I didn't have to chase after them to get them to do it. Unbelievably efficient service.
If your DS's passport has been processed, and sent out somewhere, someone, somewhere has signed for it. Is there any chance that the postman has tried to deliver it, but was unable to cause you were out (perhaps) so it's ended up at the Post Office Depot?
This happened to me once, (not a passport) and the note that the postman left had got wedged under the doormat so I couldn't see it.
I'd demand to speak to a manager at the Passport Office and demand to know if it has been sent out. If it has, it might be worth trying to contact the Post Office, I wouldn't trust the Passport Office to trace it, given their track record.